Unusual Very Strong O-H center dot center dot center dot O Hydrogen Bonding in Zinc Complex: Crystal Structure and Photoluminescence of [Zn(HL)(bpy)(2)(H2O)](2)(L) (L = O2C(CF2)(6)CO2, bpy = 2,2 ' bipyridine)

Abstract

The centrosymmetric dimer zinc compound, [Zn(HL)(bpy)(2)(H2O)](2)(L), (L = O2C(CF2)(6)CO2, bpy = 2,2'-bipyridine), was obtained through the reaction of Zn(ClO4)(2)center dot 6H(2)O, bpy and perfluorosuberic acid. Zn(II) centre is coordinated by four N atoms from two bpy ligands and two O atoms from a water molecule and monoanionic suberate ligand in a distorted octahedral coordination environment. The unit structure contains crystallographically centrosymmetric suberate anion which acts as a bidentate bridging ligand between each cationic monomer complex unit via hydrogen bonding. The very strong interaction of hydrogen bonding of hydoxycarbonyl-carboxylate system in solid state has O-H center dot center dot center dot O 2.436(3) (O center dot center dot center dot H = 1.25(6) and H center dot center dot center dot O = 1.19(6) ). These units are also connected to each other via pi center dot center dot center dot pi, C-H center dot center dot center dot pi, C-F center dot center dot center dot pi and F center dot center dot center dot F stacking interactions, C-H center dot center dot center dot O, O-H center dot center dot center dot O and C-H center dot center dot center dot F hydrogen bonds giving rise to a multi-dimensional network. The complex is the first reported example of a coordination compound based on both bpy ligands together with perfluorosuberic acid. Moreover, compound exhibit intense solid state fluorescent emissions at room temperature. The synthesis and X-ray characterization of unusual centrosymmetric dimer zinc compound, [Zn(HL)(bpy)(2)(H2O)](2)(L) (L = O2C(CF2)(6)CO2, bpy = 2,2'bipyridine), and its photoluminescence property have been reported. The very strong interaction of hydrogen bonding of hydroxycarbonyl-carboxylate system in solid state has O-H center dot center dot center dot O 2.436(4) (O center dot center dot center dot H = 1.25 (7) , H center dot center dot center dot O = 1.20(7) and OHO = 168.4A degrees).